M45

Enigma ID	M45
Name
Frequencies	3525, 4025, 4555, 4955, 5074, 5474
Status	Inactive
Voice	N/A
Emission mode	MCW (H2A)
Location	Russia
Activity pages

M45 is believed to have been a training station. The same format as M01 was used, but semi-automatically sent at the speed of about 12 words per minute. Last heard in October 2013.

Format:

Preamble				Message	Outro
525	698	30	BT BT	24669 24669 63550 63550 ... 41186 41186	BT BT	698	30	0 0 0
3-figure ID	3-figure one-time pad number?	Amount of 5-figure groups in the message		5-figure paired groups		3-figure one-time pad number?	Amount of 5-figure groups in the message
Repeated for 4 minutes	Repeated twice	Repeated twice				Repeated twice	Repeated twice

M45 was always transmitted 40 minutes before its voice counterpart S21, and sent the same message that S21 would later retransmit in voice, though sometimes M45 was transmitted on S21's schedules by mistake.

M45 used to operate on the following schedule. The transmission ID was taken from the last three digits of the lower simultaneous frequency, so for example a transmission made in January would have had the ID "525". The higher simultaneous frequency was either 400 or 500 kHz above the lower one.

Day	UTC	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Tuesday Thursday	17:02				4555 4955	5074 5474	5074 5474	5074 5474	5074 5474	4555 4955	4555 4955
Tuesday Thursday	18:02	3525 4025	3525 4025	4555 4955								3525 4025	3525 4025